Kirstie Alley learned the hard way that cutting meat from your diet is not a magic route to svelteness. As she told People magazine earlier this year, "For seven months I was a vegetarian, and I can't tell you how much weight I gained being a vegetarian!" (She actually does tell us: 83 pounds.) Indeed, while a plant-based diet has been associated with many health benefits—including a smaller risk of death from heart disease, lower LDL cholesterol levels, and a reduced incidence of diabetes, obesity, and cancer—the diet has to be "appropriately planned," as the American Dietetic Association said in its recent position statement on the subject.
What does that mean? Here are six tips to keep in mind if you’re thinking of going all—or partially—veggie.
Define what you mean by vegetarian. There are lots of variations on a vegetarian diet. Most strict are vegans, who eschew any kind of animal products, including butter and eggs. (Vegans disagree over whether to eat honey; some feel it’s cruel and exploitative of bees.) Less stringent are vegetarians who eat eggs or dairy. Some, oxymoronically, eat fish, though the accurate term for them is pescatarian. And then there are the newest additions, flexitarians, who recognize the benefits of a plant-based diet and choose to reduce but not eliminate their meat consumption. What route you go is a personal decision, depending on your tastes, preferences, and views on the environment and the proper role of animals. Think it over and figure out what fits into your life, practically and philosophically. (Here's the skinny on red meat and health.)
Remember, the root of vegetarian is “veg,” not “junk.” Some vegetarians are overweight, of course, and for reasons similar to those that cause obesity among meat-eaters. (See this blog by a vegan doctor for details.) So beware of swapping out meat for nutritionally empty, calorie-dense foods. After all, says Walter Willett, chair of the department of nutrition at the Harvard School of Public Health, a diet based on Coca-Cola, pizza, and french fries is technically vegetarian. But “the healthiest vegetarian diet will have a lot of vegetables, fruits, nuts, and legumes,” he says. At meals, half of one's plate should be devoted to nonstarchy, colorful vegetables, he says. Whole grains also are important, but confine those to a quarter of your plate. The other quarter should contain lean, plant-based sources of protein, like tofu or beans.
Replace the meat. Contrary to popular belief, it’s not particularly hard for vegetarians to get enough protein, says Dawn Jackson Blatner, a Chicago-based nutritionist and author of The Flexitarian Diet. As sources of protein, an ounce of meat and a quarter cup of cooked beans are roughly equivalent. Soy and quinoa are both good choices because they’re complete proteins, meaning they contain the essential amino acids in the right proportions. People used to think you needed to eat incomplete proteins together in the same meal to make up a complete protein, but that view has been debunked; simply eat a variety of plant-based protein sources throughout the day, and you’ll be fine. To replace the savory taste of meat, try a portobello mushroom burger, cooked tomatoes, seaweed products, and (in moderation) Parmesan cheese, says Blatner.
Watch your nutrients. Vegetarians, especially vegans, should be careful to get enough omega-3 fatty acids, iron, zinc, iodine, calcium, and vitamins D and B-12, according to the ADA. It says a balanced vegetarian diet can meet current recommendations for those nutrients. For calcium and vitamin D, consume enough dairy or a milk substitute that’s been fortified, Blatner says. The ADA also recommends leafy greens like bok choy and kale and calcium-fortified fruit juices as sources of calcium that's bioavailable (that is, in a form your body can readily use). And many breakfast cereals are fortified with vitamins D and B-12.
Zinc is found in soy products, legumes, grains, cheese, and nuts, the ADA says. As for iron, the form found in plant foods is different than what's in meat sources, and its absorption may be influenced by other components of the diet—coffee and tea inhibit absorption, while vitamin C enhances it. Good sources or iron: fortified cereal, oatmeal, lentils, beans, tofu, and spinach. (Do not take iron supplements unless your doctor recommends them.) The jury is still out on whether plant-derived omega-3s are equivalent to those from seafood sources. One way to hedge is to take an algae extract supplement to get the two forms of omega-3 that aren’t found in plants.